From 661edfc3dab943a67c8821353b63cc23057f7ce9 Mon Sep 17 00:00:00 2001 From: David Bauer Date: Tue, 9 Jan 2024 20:48:46 +0100 Subject: [PATCH] reset: ath79: read back reset register Read back the reset register in order to flush the cache. This fixes spurious reboot hangs on TP-Link TL-WDR3600 and TL-WDR4300 with Zentel DRAM chips. This issue was fixed in the past, but switching to the reset-driver specific implementation removed the old fix. Link: https://github.com/freifunk-gluon/gluon/issues/2904 Link: https://github.com/openwrt/openwrt/issues/13043 Link: https://dev.archive.openwrt.org/ticket/17839 Link: f8a7bfe1cb2c ("MIPS: ath79: fix system restart") Signed-off-by: David Bauer --- drivers/reset/reset-ath79.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/reset/reset-ath79.c +++ b/drivers/reset/reset-ath79.c @@ -37,6 +37,8 @@ static int ath79_reset_update(struct res else val &= ~BIT(id); writel(val, ath79_reset->base); + /* Flush cache */ + readl(ath79_reset->base); spin_unlock_irqrestore(&ath79_reset->lock, flags); return 0;